1. Field of the Invention
The present invention relates to an ultrasonic probe which is adapted to be put to a subject, and which transmits ultrasounds to the inside of the subject and which receives ultrasounds reflected inside of the subject. The present invention also relates to an ultrasonic diagnostic apparatus in which the ultrasonic probe is used to transmit and receive ultrasounds and images within the subject are produced and displayed in accordance with received signals derived through receiving ultrasounds with the ultrasonic probe.
2. Description of the Related Art
Hitherto, there has been used for diagnoses of diseases within the subject an ultrasonic diagnostic system in which ultrasonic beams are transmitted inside of the subject, particularly, the human body, and ultrasounds reflected at the inside of tissues in the human body and the boundary between tissue-to-tissue are received in the form of received signals, so that images in the human body involved in the received signals are formed.
Such an ultrasonic diagnostic system comprises, usually, a main frame of the ultrasonic diagnostic system and an ultrasonic probe connected through a cable to the main frame. On the tip of the ultrasonic probe, there are arranged a lot of ultrasonic transducers (e.g. 128 pieces) in which when drive signals are input, ultrasounds are transmitted in accordance with the drive signals, and the ultrasounds reflected inside the subject are picked up to generate received signals. To derive ultrasonic images within the subject, the tip of the ultrasonic probe is put to a surface of the subject. Drive signals generated in the main frame of the ultrasonic diagnostic system are fed to the ultrasonic transducers so that ultrasound is transmitted in a direction along one scan line extending within the subject and the ultrasound reflected inside the subject is picked up to generate a received signal carrying information as to the inside of the subject along the one scan line. This performance is repeated (scanned) while the scan line is shifted in a direction along which the ultrasonic transducers are arranged. In this manner, there is formed an ultrasonic image (tomographic image) within a section of the inside of the subject as to the direction along which the ultrasonic transducers are arranged. The tomographic image thus formed is displayed on an image display apparatus of the main frame of the ultrasonic diagnostic system, or may be recorded on a video tape and the like.
An ultrasonic diagnostic system is usually provided with a function of obtaining tomographic images within the subject, and in addition has a function of obtaining images representative of a blood flow distribution. However, these functions are well known in technology. Hence, there will be omitted a redundant explanation as to the image producing itself.
It happens that for the purpose of picking of a part of tissues of the affected part for a diagnosis, while an image of the affected part within the subject is formed, which is obtained with the use of the ultrasonic diagnostic system, is observed, or for the purpose of injecting medical liquid into the affected part, a puncture needle is inserted into the affected part within the subject.
There is known an ultrasonic probe for a puncture to facilitate the above-mentioned puncture operation (cf. Japanese Patent Application Laid Open Gazette Hei. 5-317309 and Japanese Utility Model Application Laid Open Gazette Hei. 5-33708). In these publication, there is proposed an ultrasonic probe for a puncture in which ultrasonic transducers, which are arranged in two directions perpendicularly intersecting each other, are provided in a unitary body, and a puncture needle guide aperture is formed so that a puncture needle may be introduced to a position at which the puncture needle appears on both two images respectively obtained through the ultrasonic transducers arranged in said two directions.
In the observation of the entire ultrasonic diagnostic works using an ultrasonic diagnostic apparatus, the puncture operation is used few times and the usual operation, such as an observation of images of the inside of the subject through moving an ultrasonic probe, is used rather much. Under such circumstances, according to the above-proposed ultrasonic probe for a puncture, the contact area to the subject is large since the ultrasonic transducers are arranged on a two-dimensional basis. This structure is suitable for operation such that the puncture needle is inserted while the ultrasonic probe for a puncture is not moved in a state that the probe is urged to a predetermined position of the subject, but is not suitable for the usual working which needs to move the ultrasonic probe. Thus, there is a need to prepare an ultrasonic probe for a usual operation in addition to preparing the ultrasonic probe for a puncture. The preparation of a plurality of types of ultrasonic probes, which are expensive, according to the presence of a puncture, causes a problem such that the cost of the ultrasonic diagnostic apparatus is increased in its entirety.